Fractal Audio AM4 Amp Modeller B-Stock
Multi-Effect Pedal for Electric Guitar
- Combines the latest Cygnus X-3 amp modelling (White Box Modelling, which simulates the individual technical and electrical components of an amplifier), DynaCab speaker simulation, UltraRes user cabinets and a comprehensive selection of high-quality effects
- The optimised user interface is modelled on traditional amplifiers and pedalboards, whilst the ‘Expert Edit’ function remains discreetly in the background and only appears when access to advanced parameters is required
- 104 presets, each with four blocks, 17 different block types and four channels per block
- Controls: Level, A, B, C, D, Select
- Buttons: Home, Save, Page Left, Page Right, Enter, Exit
- LED: High contrast colour LCD
- Footswitches: 1, 2, 3, 4
- Power consumption: 1500 mA
- Powered by a 9 V DC mains adapter (included)
- Dimensions (W x D x H): 254 x 160 x 75 mm
- Weight: 1630 g
Connectors:
- Input: 6.3 mm jack
- Insert send / return: 2 x 6.3 mm jack
- L/Mono and Right Out: 2 x 6.3 mm stereo jack
- Headphone output: 3.5 mm stereo jack
- Pedal 1 and 2: 2 x 6.3 mm stereo jack
- SPDIF input and output: 2 x RCA
- USB-C
- MIDI input and output: 3.5 mm stereo jack
- Power supply connection: Barrel connector 5.5 x 2.1 mm, centre negative
Note: Battery operation is not possible.
-
Available since July 2026
-
Item number 650676
-
Sales Unit 1 piece(s)
Compact premium modeller
With the Axe FX III, Fractal Audio has developed a highly advanced amp modelling platform, and the AM4 brings its Cygnus X-3 modelling technology, DynaCab speaker simulation, and extensive selection of effects together in a compact, saveable, and MIDI-compatible unit that is designed for straightforward operation. The simplified four-block routing system keeps the signal path clear and easy to manage, while the large display and four footswitches provide practical control for both recording and live use. Editing can be carried out directly on the unit or via USB with the AM4-Edit software, giving users additional flexibility when creating and managing sounds. The Fractal Audio AM4 can also serve as an audio interface and supports re-amping, making it suitable for a range of studio and performance applications.
)
Nothing left to chance
The Fractal Audio AM4 brings the sound and functionality of the larger models into a compact and straightforward unit, with four blocks and a stereo effects loop for integrating external equipment. At its centre is the amp block, which offers more than 240 amp channels, speaker simulation with stacked or custom impulse responses, and an additional room simulation, complemented by a graphic equaliser and boost function. The remaining slots provide access to more than 77 drive and boost effects, around 80 reverbs and delays, and approximately 150 other effect types, while 104 presets allow settings to be stored and each block can access four scenes, effectively giving every preset the functionality of a four-channel amplifier with effects. Preset changes take place almost instantaneously while retaining reverb and delay tails, and the input section also includes a noise gate and tuner for convenient day-to-day operation.
)
Focus on sound quality
The Fractal Audio AM4 is designed for users who need a compact setup capable of delivering a consistent sound on stage, in the studio, or at home. It uses the same modelling algorithms as the Axe FX III and combines them with a high-quality input stage, high-grade conversion, balanced outputs, and a powerful headphone amplifier. Connectivity includes S/PDIF, USB, and a 3.5mm MIDI interface, while the main output can also be split into separate front-of-house and monitor signals when required. The built-in USB audio interface allows both the stereo output and DI signal to be sent directly to a computer, while computer playback can be routed back to the AM4 for reamping.
)
About Fractal Audio
Founded in 2006 by Cliff Chase, Fractal Audio Systems has established itself as a prominent developer of modelling technology and effects for guitarists. Its 19-inch Axe-FX hardware is now in its third generation and has been used by artists including Steve Vai, John Petrucci and Metallica. Based in New Hampshire, the company has expanded its range over the years to include compatible remote units, the FX, AX and FM floorboards, AM amp simulation products, the compact VP4 effects processor and the X-Load load box. Fractal Audio Systems also makes selected algorithms available in plugin format, extending its modelling technology beyond dedicated hardware.
)
Ready for anything
For typical live applications, the AM4 provides a comprehensive setup with a four-channel amp and cabinet simulation, detailed adjustment options, and a broad selection of effects. The main differences compared with the larger models concern routing and connectivity rather than sound quality, while its compact dimensions make it practical for a wide range of applications, from Top 40 bands and genre-specific rigs to programmable performance setups or as a reliable backup. It is equally suited to straightforward recordings, jam sessions, and mobile use, with a central colour display, four footswitches with multi-coloured LEDs, and two expression pedal and MIDI connections providing flexible control. Overall, the AM4 combines a compact format with a broad range of functions, making it easy to integrate into different live, studio, and performance setups.
In the spotlight: Cygnus X-3 Modelling
For its amp simulation, Fractal Audio uses its proprietary Cygnus X-3 modelling process, which converts the original analogue circuitry into the digital domain and recreates it component by component to closely reproduce its characteristics. Alongside the standard user interface, which is based on the controls of the corresponding real-world amplifiers, an "Expert" mode provides access to the underlying virtual circuitry. This allows individual components to be changed, such as swapping virtual valves, replacing bright capacitors, or modifying the tone stack, giving users considerably more control over the resulting sound. The approach makes it possible to fine-tune the virtual amplifier in detail and adapt its response to individual requirements.
